This page explains how Harold E. Fredrickson (USATT# 5900)'s rating went from 1156 to 1139 at the Bill Mason Memorial Open held on - 17 Mar 2012. The links below take you to pages that describe various aspects of the rating processor.

The rating processor goes through 4 passes in order. The links take you to pages that provide detailed explanations of the calculations during each of the 4 passes.